LT1786FCS Linear Technology, LT1786FCS Datasheet
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LT1786FCS
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LT1786FCS Summary of contents
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... The LT1786F is available in a 16-pin narrow SO package. , LTC and LT are registered trademarks of Linear Technology Corporation. CCFL BACKLIGHT APPLICATION CIRCUITS CONTAINED IN THIS DATA SHEET ARE COVERED BY U.S. PATENT NUMBER 5408162 ...
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... BULB Protect Servo Voltage BAT BULB I = 100 A CCFL CCFL 100 A, I CCFL V = 1.5V CCFL TOP VIEW ORDER PART NUMBER 1 16 CCFL BULB 3 14 BAT LT1786FCS 4 13 ROYER OUT 7 10 SCL 8 9 SDA S PACKAGE 16-LEAD PLASTIC SO = 100 C, = 100 C/W JA MIN TYP MAX 6 9.5 40 100 150 ...
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... Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note calculated from the ambient temperature T J dissipation P according to the following formula: D LT1786FCS )(100 C/ Note 3: Does not include switch leakage. The denotes the specifications which apply over the full operating = 25 C ...
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LT1786F W U TYPICAL PERFORMANCE CHARACTERISTICS Supply Current vs Temperature –75 – 50 – 100 125 150 175 TEMPERATURE ( C) 1786 G01 SHDN Input ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS V Sink Offset Current C vs Temperature 10 9 CCFL CCFL CCFL –1 –2 ...
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LT1786F W U TYPICAL PERFORMANCE CHARACTERISTICS BULB Input Bias Current vs Temperature –75 – 50 – 100 125 150 TEMPERATURE ( C) 1787 G19 High-Side Sense Null Current Line Regulation ...
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... The regulator provides a separate analog ground and power ground to isolate high current ground paths from low current signal paths. Linear Technology recommends the use of star-ground layout techniques. I (Pin 2): This pin is the input to the CCFL lamp current CCFL programming circuit ...
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LT1786F PIN FUNCTIONS AGND (Pin 5): This is the low current analog ground the negative sense terminal for the internal 1.24V refer- ence and the I summing voltage in the LT1786F. CCFL Connect low current ...
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PIN FUNCTIONS ROYER (Pin 13): This pin connects to the center-tapped primary of the Royer converter and is used with the BAT pin in a floating-lamp configuration where lamp current is controlled by sensing Royer primary-side converter ...
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LT1786F W BLOCK DIAGRAM LT1786F SMBus Programmable CCFL Switching Regulator 6 SHDN SHUTDOWN + CCFL – V1 0.465V 2 I CCFL SCL 10 SMBus INTERFACE SDA 9 8 ADR 10 V BAT UNDER- THERMAL 2.4V VOLTAGE SHUTDOWN ...
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DIAGRA S t BUF SDA SCL t STOP START SMBus Write Byte Protocol, with SMBus Address = 0101101B, Command Byte = 0XXXXXXXB and Data Byte = 111111XXB ADR SMBUS ADDRESS 0 SDA 0 1 ...
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LT1786F U U APPLICATIONS INFORMATION battery drain. Additionally, all components, including PC board and hardware, usually must fit within the LCD enclosure with a height restriction of 5mm to 10mm. The CCFL regulator drives an inductor that acts as a ...
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U U APPLICATIONS INFORMATION value (see Block Diagram). A STOP condition is optional. The command code and data byte are defined with the following format: Command Code Data Byte SHDN ...
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LT1786F U U APPLICATIONS INFORMATION LT1786F SMBus Lookup Tables SMBus Address Byte Table ADR DECIMAL BINARY HEX GND 90 0101101 0101100 58 CC Bit 0 (LSB) in the SMBus Address is the Write Bit = 0 SMBus ...
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U U APPLICATIONS INFORMATION Simplified Lamp Current Programming A programming block in the LT1786F controls lamp current, permitting either grounded lamp or floating lamp configurations. Grounded configurations control lamp current by directly controlling one-half of actual lamp current and converting ...
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... This capacitor charges up when the system is first pow- ered by the battery pack wall adapter. The amount of current delivered at start-up can be very large if the total impedance in this path is small and the voltage source has high current capability. Linear Technology recommends pin provides stable loop com- C ...
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... Every aspect of the design is interrelated and any design change requires complete re-evaluation for all other critical design param- eters. Linear Technology has engineered one of the most complete test and evaluation setups for backlight designs and understands the issues and tradeoffs in achieving a compact, efficient and economical customer solution ...
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LT1786F U TYPICAL APPLICATION Dual Transformer CCFL Power Supply Space constraints may dictate utilization of two small transformers instead of a single, larger unit. Although this approach is somewhat more expensive, it can solve space problems and offers other attractive ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... SPI or Pulse Mode Programmable Peak Current Limit 1.5A, 500kHz Multiple Lamp Capability, No Lamp Flicker, Precision Maximum and Minimum Lamp Currents Maximize Lamp Life 1786fa LT/CP 0801 1.5K REV A • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 ...